Whistl Cross-Platform Sync: iOS, Android, Web

Your Whistl protection should follow you across all devices. Whether you use iPhone, Android, or web, Whistl keeps your settings, goals, partners, and progress synchronised seamlessly. This guide explains how cross-platform sync works, what data is synced, and how to set up multiple devices.

Supported Platforms

Whistl is available on all major platforms:

Mobile Apps

Web App

What Syncs Across Devices

Fully Synced Data

These items sync automatically across all your devices:

Account Settings

• Protected floor amount
• SpendingShield preferences
• Coaching style selection
• Notification settings
• Privacy preferences

Dream Board

• All goal images and videos
• Goal descriptions and target amounts
• Progress tracking data
• Milestone achievements

Accountability Partners

• Partner list and contact information
• Partner roles and permissions
• Message history
• Notification preferences per partner

Journal Entries

• All journal entries with timestamps
• Mood check-ins
• Trigger logs
• Search history and tags

Blocked Domains

• Custom blocked domain list
• DNS blocking settings
• Intervention message preferences

Transaction Data

• Connected bank accounts
• Transaction history
• Spending categories and tags
• Budget allocations

Device-Specific Data

Some data stays on individual devices:

Biometric Data

• Apple Health data (iOS only)
• Google Fit data (Android only)
• Oura Ring sync (device-paired)
• Local biometric authentication settings

Location History

• GPS location data (privacy-first: stays on device)
• Venue proximity logs
• Location-based risk patterns

App Preferences

• Display settings (dark/light mode)
• Widget configurations
• Home screen layout
• Haptic feedback preferences

How Sync Works

Sync Architecture

Sync Flow:
1. Device A makes change → Encrypted upload to Whistl Cloud
2. Whistl Cloud → Validates and stores encrypted data
3. Whistl Cloud → Pushes notification to Devices B, C, D
4. Devices B, C, D → Download and decrypt changes
5. All devices → Updated within 5 seconds typical

Encryption:
- Data encrypted on device before upload (AES-256)
- Encrypted in transit (TLS 1.3)
- Encrypted at rest on servers
- Only your devices can decrypt

Sync Timing

Conflict Resolution

When the same data is modified on multiple devices simultaneously:

• Last-write-wins: Most recent change takes precedence
• Timestamp-based: Server timestamps determine order
• Field-level merging: Different fields on same record don't conflict
• User notification: Alerted if significant conflict detected

Setting Up Multiple Devices

Add a Second Device

1. Download Whistl on your second device (iOS, Android, or access web app)
2. Sign in with the same account credentials
3. Complete authentication (2FA if enabled)
4. Wait for initial sync (typically 30-60 seconds)
5. Verify data Check that goals, partners, and settings appear

Device Management

View and manage connected devices:

1. Go to Settings → Devices
2. See list of all devices with last sync time
3. Tap any device to see details
4. Swipe to remove devices you no longer use

Device Limits

Web App Features

The Whistl web app (app.whistl.app) provides full access from any browser:

Available on Web

• Dashboard with spending overview
• Dream Board management
• Journal entries and mood tracking
• Partner messaging
• Transaction history and categorisation
• Settings and account management
• Data export (Premium)
• Reports and analytics (Premium)

Mobile-Only Features

• Real-time location-based alerts
• Biometric integration (HealthKit, Google Fit)
• DNS-level gambling blocking
• Push notifications for interventions
• Face ID/Touch ID app lock
• Offline mode functionality

Best Use Cases for Web

• Desktop budget review and planning
• Detailed transaction categorisation
• Export and analyse data
• Partner messaging from computer
• Goal management with larger screen

Sync Troubleshooting

Common Issues

Manual Sync

Force a sync manually:

1. Pull down on the main dashboard
2. Release when you see "Syncing..."
3. Wait for "Synced" confirmation
4. Changes should now appear on all devices

Privacy and Security

End-to-End Encryption

• All synced data encrypted before leaving your device
• Encryption keys stored only on your devices
• Whistl servers cannot decrypt your data
• Even if servers compromised, your data remains private

Sync Security Features

• Device authentication required for sync
• New device alerts sent to existing devices
• Remote device wipe capability
• Automatic logout after 90 days inactivity

Bandwidth and Data Usage

Typical monthly sync usage: 50-200 MB depending on usage patterns.

Conclusion

Whistl's cross-platform sync ensures your behavioural finance protection follows you everywhere. Set up once, access from any device, and trust that your data is synchronised securely and privately. Whether you're on iPhone, Android, or web—Whistl is always there.

Related: Offline Mode | Data Security & Privacy | All Whistl Features